A galvanometer gives full scale deflection with $0.006$ A current. By connecting it to a $4990 \ \Omega$ resistance, it can be converted into a voltmeter of range $0-30 \ V$. If connected to a $\frac{2 n }{249} \Omega$ resistance, it becomes an ammeter of range $0-1.5 \ A$. The value of $n$ is:
  • A$2$
  • B$3$
  • C$4$
  • D$5$
IIT 2014, Diffcult
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